About 100 radial canals, 3-6 times as many tentacles; tentacle bulbs laterally compressed. Umbrella up to 145 mm wide, usually 60-80 mm, low and thick manubrium, about half as wide as umbrella; gonads extending along almost whole length of radial canals; numerous small bulbs; all bulbs with excretory papillae; statocysts numerous, crowded.